McCain lowers debate expectations

Arizona Sen. John McCain sought to lower debate expectations for Mitt Romney on Sunday, arguing that most presidential forums did not offer a breakthrough opportunity for either candidate.

"Sometimes we expect a major breakthrough, but that doesn't happen very often," McCain said on CNN's "State of the Union."

McCain, who as the Republican presidential nominee faced off against Barack Obama in three debates in 2008, said that the candidates would be rehearsed and would be able to anticipate most of the questions asked.

Romney, now a decided underdog in this presidential race, is looking for a big moment in the debates - the first of which is being held on Wednesday in Denver.